I have seen on ebay Teramoto Premium Finish Finemet DAC chip Direct Output Transformer for AKM AK4399/4396 Pair US $1,030.00 🙂
The saller says: "Our Finemet Direct DAC output transformer is specially designed for each DAC chip. These transformers will provide VERY GOOD three dimensional image and sound stage that will blow your socks off!!!"
Hi Valeri: for such cost it would blow my wallet off!!! 🙂
dookie182: I didn't used them yet as I wasn't sure about what to expect from them in AKM combo and after Valeri confirmed only slight difference between his UTC A20 and HDAM modules I might sell them at the end...instead of additional upgrades on AKM DAC I bought this baby 😉
dookie182: I didn't used them yet as I wasn't sure about what to expect from them in AKM combo and after Valeri confirmed only slight difference between his UTC A20 and HDAM modules I might sell them at the end...instead of additional upgrades on AKM DAC I bought this baby 😉
So it's the start of a new story. Are you expecting it to behave on the same level of sonic refinement? Very sexy baby anyways. I'll be keeping an eye on your progress.
Best regards
Best regards
Hi Kukynas,
What for you bought this one? As far as i understood you were happy with the Ak4399 DAC. I am just courious.
dookie182: will post my findings end of this week 😉
Hi Valeri,
I didn't want to mess around with tube output in AKM board as the result might be worst and cost more than completed DAC made with tube output and I'm glad I did.
There's nothing wrong with AKM DAC and discrete output stage but it reached it's limits, my purpose was build it, tweak it as much as I could without any damage to the board and chassis and find out what it is capable of, I knew since the beginning this is not my last DAC 😉
Hi Valeri,
I didn't want to mess around with tube output in AKM board as the result might be worst and cost more than completed DAC made with tube output and I'm glad I did.
There's nothing wrong with AKM DAC and discrete output stage but it reached it's limits, my purpose was build it, tweak it as much as I could without any damage to the board and chassis and find out what it is capable of, I knew since the beginning this is not my last DAC 😉
Hello, guys.
I finish collecting board DAC and I was left with a few questions. On board display, not a transistor. His feet on the board shorted?
In the DAC board is zener (or diodes?) Near the transistors in power operational amplifiers. Can you tell me their labeling, the brand? I sent them or not, or I lost them.
I finish collecting board DAC and I was left with a few questions. On board display, not a transistor. His feet on the board shorted?
In the DAC board is zener (or diodes?) Near the transistors in power operational amplifiers. Can you tell me their labeling, the brand? I sent them or not, or I lost them.
Hi Kukynas,
I understood your reason. I am currently using transformer output for one simple reason: transformer prevents ground loop which exists with OPAs and HDAMs due to my mistake in grounding of stereo power amplifier. The ground loop causes small hum. I know how to correct it but I don’t want to open the amplifier now. I am very happy how my system sounds now. I already inserted the DAC board in case of my pre-amplifier and enjoy listening to music.
In future I am going to replace OPAs by … power amplifier with balanced input and in fact completely pass by analogue stage of the DAC. I am building amplifier “Aleph J” of Mr. Nelson Pass as mono blocks. As you can see of the picture it is still long way to go. It has schematic like an OPA but with class A Single Ended output stage. I will connect potentiometer of volume control directly to DAC outputs as shown on the attached picture. Amplifier with balanced input is not sensitive to hum on IN+ and IN- wires, consequently I don’t need a buffer with low output impedance between middle point of volume control potentiometer and power amplifier in order to minimize hum. The mono blocks will be placed right behind speakers and length of speaker wires will be just 10 cm. I like minimalist approach.
I understood your reason. I am currently using transformer output for one simple reason: transformer prevents ground loop which exists with OPAs and HDAMs due to my mistake in grounding of stereo power amplifier. The ground loop causes small hum. I know how to correct it but I don’t want to open the amplifier now. I am very happy how my system sounds now. I already inserted the DAC board in case of my pre-amplifier and enjoy listening to music.
In future I am going to replace OPAs by … power amplifier with balanced input and in fact completely pass by analogue stage of the DAC. I am building amplifier “Aleph J” of Mr. Nelson Pass as mono blocks. As you can see of the picture it is still long way to go. It has schematic like an OPA but with class A Single Ended output stage. I will connect potentiometer of volume control directly to DAC outputs as shown on the attached picture. Amplifier with balanced input is not sensitive to hum on IN+ and IN- wires, consequently I don’t need a buffer with low output impedance between middle point of volume control potentiometer and power amplifier in order to minimize hum. The mono blocks will be placed right behind speakers and length of speaker wires will be just 10 cm. I like minimalist approach.
Attachments
730user: I don't understand, which transistors? can you show it on the picture? btw, do you have board schematics?
Hi Valeri,
interesting approach, what are your expectations of it? do you also plan to change your speakers to squeeze maximum out of it?
Hi Valeri,
interesting approach, what are your expectations of it? do you also plan to change your speakers to squeeze maximum out of it?
Hi Kukynas,
I hope that skipping analog stage of the DAC will give noticeable improvement. As I already mentioned I use transformer in order to convert balanced output of the DAC to unbalanced input of my power amplifier. Although the UTC A20 transformer is very good it is not ideal. The same applies to HDAM modules and different tube stages. I will remove transformer as soon as will finish new amplifier with balanced input. Obviously the less unnecessary electronic components in audio signal path the better.
YES, I have a plan to change speakers. During last summer I made quick & dirty clone of Lampizator’s Endorphin P19 out of available under hand materials. Although size of wooden panels were smaller than recommended the results were promising and I decided come back to this project after new finishing amplifier.
I hope that skipping analog stage of the DAC will give noticeable improvement. As I already mentioned I use transformer in order to convert balanced output of the DAC to unbalanced input of my power amplifier. Although the UTC A20 transformer is very good it is not ideal. The same applies to HDAM modules and different tube stages. I will remove transformer as soon as will finish new amplifier with balanced input. Obviously the less unnecessary electronic components in audio signal path the better.
YES, I have a plan to change speakers. During last summer I made quick & dirty clone of Lampizator’s Endorphin P19 out of available under hand materials. Although size of wooden panels were smaller than recommended the results were promising and I decided come back to this project after new finishing amplifier.
Hi Valeri,
open baffle is known and not that expensive system but requires proper match of drivers and crossover design otherwise it might become big disappointment same as horn speakers without proper cabinet and placement in the room, I have no place in my living room for such speakers so I wouldn't even thinking about that but prior to purchase of my Focals I was thinking about CNO-25 project, at the end when I calculated cost of it I decided to go known path with Focals...
Anyway good luck with it 😉
open baffle is known and not that expensive system but requires proper match of drivers and crossover design otherwise it might become big disappointment same as horn speakers without proper cabinet and placement in the room, I have no place in my living room for such speakers so I wouldn't even thinking about that but prior to purchase of my Focals I was thinking about CNO-25 project, at the end when I calculated cost of it I decided to go known path with Focals...
Anyway good luck with it 😉
OCC Power transformer
The long awaited power transformer with OCC silver plated secondary eventually arrived. It does not take much time to install it together with the MCap Silver/Gold/Oil output capacitors and the result is excellent. The frequency range of UTO extended at both ends while the bass is getting more tenacious; especially with double bass. The opamp's performance also improved but is not as significant as UTO.
I planned to install a toggle switch to select tube or opamp output but after listening for a while, it is not necessary as the tube output out-performs the opamp section by far distance.
I think this would be the end of my tweak to this DAC although I have not try transformer output yet. Since; as mentioned, the UTC A20 performance is comparable to that of HDAM, I think the UTO will beat transformer output at the same distance as HDAM in my system.
The long awaited power transformer with OCC silver plated secondary eventually arrived. It does not take much time to install it together with the MCap Silver/Gold/Oil output capacitors and the result is excellent. The frequency range of UTO extended at both ends while the bass is getting more tenacious; especially with double bass. The opamp's performance also improved but is not as significant as UTO.
I planned to install a toggle switch to select tube or opamp output but after listening for a while, it is not necessary as the tube output out-performs the opamp section by far distance.
I think this would be the end of my tweak to this DAC although I have not try transformer output yet. Since; as mentioned, the UTC A20 performance is comparable to that of HDAM, I think the UTO will beat transformer output at the same distance as HDAM in my system.
Attachments
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That looks great Sunsun22.
I agree my tube output is better in every way.
I didn't do a toggle switch but done two sets of outputs one from tube output and one from op amp outputs.
Then I connected two sets of leads to my amp on different inputs so I could switch between the two outputs from dac.
The tube outputs have a much bigger soundstage and fill my room better.
I copied my tube output from the lampizator site with dual mono and dual tubed psu.
I guess I'm lots like you people, I have bought mine all in parts and assembled everything with my own parts choice. Realized also how many fake parts are in the kit... Look at the Elna Silmic II... They're supposed to be brown with white letters but they are black with gold letters, etc...
Anyways, replaced all through hole resistors with PRP and Takman Rey, replaced all SMD ceramic caps with MLCC COG type and resistors to Susumu 0.01%, the axial caps to polymer OS-Con type, small pF caps in the filter to Amtrans AMCH and replaced all regulators with new ones since I realized some of them are used pulls and since I didn't know how they were used in their previous life, I decided to replace all.
Also, my friend Fab has completely redone the output filter calculations based on the AKM technical specifications
So here it is
12k --> 10k
8k2 --> 5k1
3k3 --> 1k3
100pF --> 300pF
390pF --> 680pF
You can go here to see my build
Dual AK4399
So far I really enjoy this DAC, price is good and music too! 😀
One question... I want to connect the WaveIO instead of the Xmos they sell (better support and drivers) and I wanted to know if anyone knew the pinout of the 7 pin header on the PCB so I could connect the WaveIO card directly to it?
Also, the LCD backlit on my display won't fire on... I can only read 0.7V on the LED terminal of it. Anyone has an idea? I can still see the writing but no backlit
Thanks
Do
Anyways, replaced all through hole resistors with PRP and Takman Rey, replaced all SMD ceramic caps with MLCC COG type and resistors to Susumu 0.01%, the axial caps to polymer OS-Con type, small pF caps in the filter to Amtrans AMCH and replaced all regulators with new ones since I realized some of them are used pulls and since I didn't know how they were used in their previous life, I decided to replace all.
Also, my friend Fab has completely redone the output filter calculations based on the AKM technical specifications
So here it is
12k --> 10k
8k2 --> 5k1
3k3 --> 1k3
100pF --> 300pF
390pF --> 680pF
You can go here to see my build
Dual AK4399
So far I really enjoy this DAC, price is good and music too! 😀
One question... I want to connect the WaveIO instead of the Xmos they sell (better support and drivers) and I wanted to know if anyone knew the pinout of the 7 pin header on the PCB so I could connect the WaveIO card directly to it?
Also, the LCD backlit on my display won't fire on... I can only read 0.7V on the LED terminal of it. Anyone has an idea? I can still see the writing but no backlit
Thanks
Do
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Hi Pinnocchio I had the same problem of display light not working.
I am away now till Monday so I will check what I did to solve this when I get home.
By memory it was to do with the remote sensor being missing on the display pcb.
I bridged it across or something.
The resistor long ways by the white plugs feeds the power to the display light just round the corner to where this sensor should be feeds the display light.
Basically you need the 5v from where this sensor should be to feed that resistor.
Hi pinnocchio
I bought recently Xmos module. In the description I found following
"USB-DM" connect to " D- " of the USB; "USB-DP" connect to " D+ " of the USB; VBUS is also connect to usb
>>7 pins: 1 (VBUSE); 2(USB-DM) ; 3(USB-DP) ; 4 ; 5(S1) ; 6(GND) ; 7(S1A)
(S1 is coaxial signal out, and regarding the S1A, just leave it there)
Thanks in advance for letting me know. In the meantime, I will tinker with it.
Ciao!
Do
Hi Valeri,
are those PCB pins directly compatible in sequence with xmos module? I bought same module just re-solder pins to accommodate it directly on existing PCB socket just don't know if the pin out matches attached like this
with cmos card installed - My Photo Gallery
are those PCB pins directly compatible in sequence with xmos module? I bought same module just re-solder pins to accommodate it directly on existing PCB socket just don't know if the pin out matches attached like this
with cmos card installed - My Photo Gallery
Hi Valeri100,
I'm sure that on the DAC PCB there's pins for mclk, dck, lrck, etc... This xmos module has to be connected using I2S, it would be stupid not to anyways. So there should be a GND, the USB data pins + the 5v and the rest of the pins should be I2S related... Just a wild guess of course... 😀
Ciao!
Do
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